Origin 1.2 and Enterprise 1.2 are the same Docker distribution version, v2.2. They also use the same s3 driver, so I wouldn't expect a difference. I don't think anyone has tested sydney, but I would not be surprised if the S3 client driver does not fully support that region at the point in time we snapshotted it. The fact that us-east worked makes me suspicious.

Is S3 v4auth supported in the sydney region? That is the first thing that comes to mind. The public docker image for the registry is a bit newer than the registry in Origin, so it's possible as well that the S3 driver was updated between that registry and v1.2.0. No registry changes were made in origin between v1.2.0-rc1 and v1.2.0, so I suspect the change is related to S3 config, not the registry code.

I've spent the past two days looking at the problem of s3 backed storage from Sydney based instances. The problem now appears to be more generally associated with S3 backed registries in the ap-southeast-2 region.

With configurations identical other than keys/bucket/region the results are considerably different.